Quarterly report pursuant to Section 13 or 15(d)

Debt Instruments - Convertible Debt Offering (Details)

v3.7.0.1
Debt Instruments - Convertible Debt Offering (Details) - USD ($)
Dec. 09, 2015
Mar. 31, 2017
Debt Instruments    
Closing price of common stock (in dollars per share)   $ 11.81
Convertible debt | Notes    
Debt Instruments    
Aggregate principal amount $ 345,000,000.0  
Interest rate 1.75% 1.75%
Net proceeds from sale of debt $ 336,500,000  
Payments for capped call transactions $ 43,200,000  
Debt instrument, conversion price (in dollars per share) $ 16.42  
Value of debt   $ 333,700,000